Oleg Kobchenko wrote:
> there are three bottlenecks in new OpenGL:
> 
>  - blting: is OK for Win for medium window size, for full screen
>    it's more than 3 times lower, but is much 
>    worse in Java possibly due to Java bridge
>    (to test use full screen with simple model)

I don't know about windows, but in principle for linux this could 
be resolved by using a different opengl library.  (This would also 
require a different alloc and a different procedure for updating 
the display.)

However, I don't know enough about the isigraph control's
internal implementation to know what this would mean for
the traditional "opengl gets rendered in an isigraph control"
approach.

>  - cost of call: this has been improved and looks like works
>    event better than in j504.

This, of course, is wonderful.

> - not using lists (this I just discovered as new potential problem)
>   It is very bad on vertex intensive models:
>   x2-x4 slower from j504 (to test use small window with
>   complex mode, eg Dini -- hold 'x' and count seconds of full flip).

I think this can be addressed by using pixels_keep and keeping
alloc out of the paint event.  (Only use alloc initially, and
when the window changes size.  And, recreate command lists after 
using alloc.)

If a different opengl library is used, this basic pattern would
still apply (keep alloc and free out of the paint event).

> Where I learnt that there are vertex arrays (might be platform speciffic).

According to
 http://www.opengl.org/resources/faq/technical/extensions.htm
these are part of the 1.1 standard (and as I understand it, J
has always required opengl to be at least version 1.1).

J5.4 did not support vertex arrays, but that was a J issue, not
an opengl issue.

> But it's on those models that contain huge amount of vetices that
> may benefit.

Note also that vertex arrays offer a very different sort of
abstraction than command lists.  They seem to be suitable for
different classes of problems.

-- 
Raul

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